In conventional dump truck design, a truck operator usually upon reaching the dump site is first required to adjust the tailgate chains which limits the amount the tailgate opens during the dumping operation. The operator then returns to the cab and via the console unlatches the tailgate, elevates the truck box and begins the application of material from the truck box.
However, if the adjustment of the tailgate chains was incorrect, if the chains had become entangled, or if something in the material was restricting discharge of the material from the truck box, the operator would then be required to leave the cab to readjust or disentangle the chains, or clear the restriction impeding the flow of material from the truck box. Since the truck box is elevated, the material load within the truck box is now applying pressure to the tailgate chains, and it becomes almost impossible to adjust the chains without shifting the material within the truck box (lowering the truck box) away from the tailgate.
In the event the operator attempts to adjusts the chains without shifting the load (lowering the box), severe injury to the operator may result due to the forces involved. In order to readjust the chains, the operator must be standing at the rear end of the truck. When an operator attempts to readjusts the chains, the operator's focus is changed from operating an entire material handling system (dump truck) to making a point of application adjustment (adjusting the tailgate). When the operator is required to leave the cab, the operator is much more vulnerable to ground traffic. Further, when making such a readjustment of the tailgate chains, the operator may also give up a strategic vantage point thereby losing sight of the overall conditions developing around the operating environment.
The amount of man and equipment hours lost in adjusting the tailgates of conventional dump trucks is a major consideration. The hours lost in adjusting and readjusting the tailgate in these conventional dump trucks are impossible to recover.